Throbak Overdrive Boost

Features:
* 3 Carefully selected TO-18 metal can Silicon transistors, as used in the original circuit.
* Externally switchable pre gain control with internal pot allowing you to dial in the best pre gain for your guitar.
* Switchable Germanium transistor and Germanium diode pair.
* Bias adjustment for transistors ensuring a perfectly tuned pedal.
* Master volume & true bypass footswitch.
* Gain, Bass and Treble adjustment.

https://www.throbak.com/overdrive-boost-overdriver-power-boost.html